The invention relates to a fuel injection system for mixture-compressing and externally ignited internal combustion engines. The fuel injection system meters out a quantity of fuel in proportion to the aspirated combustion air and at the same time serves to insure uniform distribution and adequate preparation of the metered out fuel within the aspirated air. More particularly, the invention relates to a fuel injection system which employs continuous injection of fuel into the induction tube and in which the induction tube contains an air flow rate meter and, located behind it, an arbitrarily actuated throttle plate. The air flow rate meter has an axially movable member which is subject to a restoring force and displaces the movable part of a fuel metering valve. In a known fuel injection system of this general type, a sensor pin associated with the fuel metering valve outside of the induction tube senses the position of the air flow rate measuring member and provides no further preparation of the fuel which is simply delivered to the injection valves and introduced into the engine just ahead of the intake valves. This type of system results in substantial constructional expenditure and the relatively poor preparation of the fuel-air mixture causes the exhaust gases to contain undesirably high components of toxic materials and also results in a reduction of the engine power due to the uncombusted fuel.